ARM: SAMSUNG: Add support for 12bit ADC

The S3C64XX SoC series support 12bit ADC data, enable this and
mask the data accordingly.

Signed-off-by: Maurus Cuelenaere <mcuelenaere@gmail.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>

2 files changed, 20 insertions, 5 deletions

diff --git a/arch/arm/plat-samsung/adc.c b/arch/arm/plat-samsung/adc.c
index c7659b7378b1..81caf2135721 100644
--- a/arch/arm/plat-samsung/adc.c
+++ b/arch/arm/plat-samsung/adc.c
@@ -262,6 +262,7 @@ static irqreturn_t s3c_adc_irq(int irq, void *pw)
 {
         struct adc_device *adc = pw;
         struct s3c_adc_client *client = adc->cur;
+        enum s3c_cpu_type cpu = platform_get_device_id(adc->pdev)->driver_data;
         unsigned long flags;
         unsigned data0, data1;
 
@@ -276,9 +277,17 @@ static irqreturn_t s3c_adc_irq(int irq, void *pw)
 
         client->nr_samples--;
 
+        if (cpu == TYPE_S3C64XX) {
+                /* S3C64XX ADC resolution is 12-bit */
+                data0 &= 0xfff;
+                data1 &= 0xfff;
+        } else {
+                data0 &= 0x3ff;
+                data1 &= 0x3ff;
+        }
+
         if (client->convert_cb)
-                (client->convert_cb)(client, data0 & 0x3ff, data1 & 0x3ff,
-                                     &client->nr_samples);
+                (client->convert_cb)(client, data0, data1, &client->nr_samples);
 
         if (client->nr_samples > 0) {
                 /* fire another conversion for this */
@@ -295,7 +304,7 @@ static irqreturn_t s3c_adc_irq(int irq, void *pw)
         }
 
 exit:
-        if (platform_get_device_id(adc->pdev)->driver_data == TYPE_S3C64XX) {
+        if (cpu == TYPE_S3C64XX) {
                 /* Clear ADC interrupt */
                 writel(0, adc->regs + S3C64XX_ADCCLRINT);
         }
@@ -308,6 +317,7 @@ static int s3c_adc_probe(struct platform_device *pdev)
         struct adc_device *adc;
         struct resource *regs;
         int ret;
+        unsigned tmp;
 
         adc = kzalloc(sizeof(struct adc_device), GFP_KERNEL);
         if (adc == NULL) {
@@ -354,8 +364,12 @@ static int s3c_adc_probe(struct platform_device *pdev)
 
         clk_enable(adc->clk);
 
-        writel(adc->prescale | S3C2410_ADCCON_PRSCEN,
-               adc->regs + S3C2410_ADCCON);
+        tmp = adc->prescale | S3C2410_ADCCON_PRSCEN;
+        if (platform_get_device_id(pdev)->driver_data == TYPE_S3C64XX) {
+                /* Enable 12-bit ADC resolution */
+                tmp |= S3C64XX_ADCCON_RESSEL;
+        }
+        writel(tmp, adc->regs + S3C2410_ADCCON);
 
         dev_info(dev, "attached adc driver\n");
 
diff --git a/arch/arm/plat-samsung/include/plat/regs-adc.h b/arch/arm/plat-samsung/include/plat/regs-adc.h
index f43c8dab39e4..7554c4fcddb9 100644
--- a/arch/arm/plat-samsung/include/plat/regs-adc.h
+++ b/arch/arm/plat-samsung/include/plat/regs-adc.h
@@ -25,6 +25,7 @@
 
 
 /* ADCCON Register Bits */
+#define S3C64XX_ADCCON_RESSEL           (1<<16)
 #define S3C2410_ADCCON_ECFLG            (1<<15)
 #define S3C2410_ADCCON_PRSCEN           (1<<14)
 #define S3C2410_ADCCON_PRSCVL(x)        (((x)&0xFF)<<6)